Multimodality imaging of atherosclerotic plaque activity and composition using FDG-PET/CT and MRI in carotid and femoral arteries

• Published in: Atherosclerosis Vol. 207; no. 1; pp. 139 - 143
• Main Authors: Silvera, Stephane S, Aidi, Hamza el, Rudd, James H.F, Mani, Venkatesh, Yang, Lingde, Farkouh, Michael, Fuster, Valentin, Fayad, Zahi A
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ireland Ltd 01.11.2009; Elsevier
• Subjects: Aged; Atherosclerosis; Atherosclerosis (general aspects, experimental research); Atherosclerosis - diagnosis; Atherosclerosis - metabolism; Biological and medical sciences; Blood and lymphatic vessels; Calcium - analysis; Cardiology. Vascular system; Cardiovascular; Carotid Artery Diseases - diagnosis; Carotid Artery Diseases - metabolism; Carotid artery diseases/radionuclide imaging; Collagen - analysis; Female; Femoral Artery - chemistry; Femoral Artery - diagnostic imaging; Femoral Artery - pathology; Femoral artery diseases/radionuclide imaging; Fluorodeoxyglucose F18; Fluorodeoxyglucose F18/diagnostic use; Humans; Inflammation - diagnosis; Inflammation - metabolism; Inflammation/diagnosis/radionuclide imaging; Lipids - analysis; Magnetic Resonance Angiography; Magnetic resonance imaging; Male; Medical sciences; Middle Aged; Necrosis; Positron Emission Tomography/Computed Tomography imaging; Positron-Emission Tomography - methods; Predictive Value of Tests; Prospective Studies; Radiopharmaceuticals; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Tomography, X-Ray Computed; Vascular surgery: aorta, extremities, vena cava. Surgery of the lymphatic vessels; Magnetic resonance imaging; Humans; Atherosclerosis; Inflammation/diagnosis/radionuclide imaging; Positron Emission Tomography/Computed Tomography imaging; Carotid artery diseases/radionuclide imaging; Fluorodeoxyglucose F18/diagnostic use; Femoral artery diseases/radionuclide imaging; Human; Tomography imaging; Femoral artery; Cardiovascular disease; Positron Emission Tomography/Computed; Inflammation; Nuclear magnetic resonance imaging; Vascular disease; Atherosclerotic plaque; Blood vessel; Carotid; Computerized axial tomography; Circulatory system; Diagnosis; Positron emission tomography; Emission tomography
• ISSN: 0021-9150; 1879-1484
• DOI: 10.1016/j.atherosclerosis.2009.04.023

Abstract Purpose To evaluate the relationship between atherosclerotic plaque inflammation, as assessed by FDG-Positron Emission Tomography/Computed Tomography (FDG-PET/CT), and plaque morphology and composition, as assessed by magnetic resonance imaging (MRI), in the carotid and femoral arteries. Materials and methods Sixteen patients underwent FDG-PET/CT and MRI (T2-weighted (T2W) and proton density weighted (PDW)) of the carotid and femoral arteries. For every image slice, two observers determined the corresponding regions of the FDG-PET/CT and MRI image sets by matching CT and T2W axial images. Each plaque was then classified into one of three groups according to the CT appearance and T2W/PDW signal: (1) collagen, (2) lipid-necrotic core and (3) calcium. Arterial FDG uptake was measured for each plaque and normalized to vein FDG activity to produce a blood-normalized artery activity called the target to background ratio (TBR). The vessel wall thickness (VWT), the vessel wall area and the total vessel wall area were measured from the T2W MR images. Results The TBR value was higher in the lipid-necrotic core group compared to the collagen and calcium groups, ( p < 0.001). The lipid-necrotic core group demonstrated a significant TBR variation according to the median of the VWT (TBR = 1.26 ± 0.25 vs. 1.50 ± 0.12). There was no correlation with other morphological MR parameters. Conclusions This study demonstrates the complementary value of non-invasive FDG-PET/CT and MR imaging for the evaluation of atherosclerotic plaque composition and activity. Lipid-rich plaques are more inflamed than either calcified or collagen-rich plaques.